Refrigerating apparatus



Get. 15, 1935. s. A. LIMPERT 2,01%7925 REFRIGERATING APPARATUS Filed Dec. 9, 195s 2 sheets-sheet 1 "w l z a -a Z C' vENToR: N

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@ci 15, i935. 5 A, UMPERT 2,017,215

REFRIGERATING APPARATUS Filed Deo. 9, 1933 2 Sheets-Sheet 2 film! HIIWHIIA INVENTORZ ATTORNEY,

Patented Oct. 15, 1935 UNITED STATES PATENT OFFICE 2,017,215 REFRIGERATING APPARATUS Sylvester A. Limpert, Bay to Mechana Kold Corporation,

Shore, N. Y., assignor Bay Shore,

21 Claims.

This invention relates to refrigerating apparatus and more particularly to that type known as domestic refrigerating apparatus having an evaporator unit in the low side of the system in which is positioned trays for the production of orator.

ice cubes or for frozen desserts and the like and has for its principal objects the provision of a sturdy, efficient and yet simple, economical and cheap tray-lifting or tray loosening device for fracturing the ice bond between the tray and the underlying support on the evaporating unit carrying the same without in any way interfering with the insertion of a tray into such evaporator unit, whereby the tray can be readily and repeatedly released from its support without any possi- ,bility of imparting deleterious strains on the parts of the evaporator and the refrigerant line connections thereto with the possibility of consequent leakage of the refrigerant at the points of juncture of the refrigerant line with such evap- Other advantages are hereinafter set forth.

Heretofore, as disclosed in Patent No. 1,838,954, it has been proposed to effect the separation of a tray from its support to which it may become adhered by reason of the freezing of condensed moisture between such tray and support by providing a lever or wedge element, the handle of which is adapted to be manipulated from a point outside of a front baffle plate concealing such tray and which was adapted tc pry said tray off of the said support. However, when a lever was employed in order to obtain effective leverage, it is not only necessary, owing to the high pressure required, to provide an objectionably long lever,

but the lever was so mounted that the pressure l reaction from the movement thereof strained or tended to displace the support with respect to the refrigerant line connections, with the result that frequently under repeated operation thereof such movement of the support tended to cause leaks to develop at the joints between the refrigerant supply conduit and the support proper, through which latter the refrigerant medium circulated. Y Moreover, according to the disclosure of the said patent, where wedges are to be employed, it is proposed to employ ribs or beads on the underlying support, in order not only to provide an entrance for such wedge or lever arm, but to facilitate movement of the tray when pressure is applied to the front end thereof.

Moreover, according to the disclosure of Patent No. 1,893,535, it has also been proposed to provide a camming device adapted to apply pressure on one end of a tray whereby the same was caused to slide longitudinally on longitudinal ribs formed on the supporting slides or ribs. tion also is objectionable because, as stated, one of the aforesaid prime essentials of ice cube freezing, namely intimate contact between the support and the tray has been destroyed by the prvision of such rib-like construction and furthermore as such cam element is arranged to operate upon an integral flange provided on the front end of the grid member, the resulting camming action was far less effective, due to the resiliency thereof, than where, as in my present construction, the upper end of the square threaded screw member engages directly the rigid bottom of the tray.

1t has even been proposed, in order to obviate the damage often resulting from the operation of mechanical loosening of the trays as set forth in Patent No. 1,819,324, to provide electrical heating means having heating elements which are disposed between the bottom of the tray and the supporting shelf, the same usually comprising a at insulating heating element whereby the ice bond formed between the tray and the shelf or support would be melted and the tray becomes loosened by switching on the current for a brief period. Such electrical devices are not only eX- pensive to install, but frequently break down in operation, due to failure of the heating element or to defects in the electrical connections thereto, but such heating elements of themselves defeat one of the prime essentials of ice cube freezing, namely the provision of an intimate electric contact between the supporting shelf rand the metal tray, thereby greatly prolonging the freezing period.

In the accompanying drawings I have illustrated a. preferred embodiment of my invention as applied to a freezing or evaporator unit of a domestic refrigerating machine, which unit is of the so-called pressed-coil type, such for example as described in my prior Patents Nos. 1,862,154 and 1,929,952.

Referring to the shown therein,

Figure l is a vertical, transverse section of an' evaporator unit, the tray and certain parts of such unit being shown in elevatio-n and which drawings and construction Such a construcunit is equipped with my improved tray lifting device.

Fig. 2 is a longitudinal vertical section on the line 2-2 of Fig. 1, with the tray shown in elevation.

Fig. 3 is a on the line fragmentary bottom plan view, viewed 3-3 of Fig. 2, the operating handle 55 Referring to the drawings and the construc-l tion shown therein, the reference numeral I designates the main shell of an evaporator, the same preferably being provided, as shown, with anv integral bottom 2 adapted to serve as a support for trays a and b. A pressure plate 3 serves to hold compressed refrigerant coils 4 in intimate contact with the bottom 2 of the unit whereby the eflicient heat exchange between the refrigerant vin said coils and the metal bottom of the evaporator unit or tray support is accomplished. Said bottom element 2, as shown, is provided with a boss 5 which is integrally formed thereon preferably being cast therewith. The said lug and bottom plate are drilled toy form a cylinder 5 for the reception of a plunger 'I that is provided intermediate its ends 8 and 9 respectively with a spiral groove c of a relatively long pitch, which co-operates with a set screw Eil whose inner end d is Y preferably of considerably reduced section and is of a diameter substantially equal to the width of the groove c. The lower end 9 of said plunger is tapped tc receive the end of a handle member i I which has a terminal knob I2 preferably formed of bakelite or other like ornamental composition material I2. A coil spring I4, which is secured by one of its ends to the handle II and by its other end to a screw I5 that extends through said pres- F sure plate and is anchored in a tapped recess in said bottom 2, serves to normally retain the plunger 6 in a depressed position and to return the same to that position, from the tray lifting position shown in Fig. 3, when the requisite manual pressure, necessary to eifect the fracture of the ice bond between the tray and its support have been relieved. The handle I Iy may either be of sucient length to extend completely through the slot e in the front baille plate I6, so that the terminal knob may be accessible from the front of the baifle plate, or if preferred, a shorter handle may be provided and accessibility had thereto by reaching beneath the baffle plate.

In the modification illustrated in Fig. 5 and Fig. 6, an evaporating unit of generally similar design to that shown in Figs. l and 2, is equipped with a sealing diaphragm which prevents the downward seepage of moisture from the tray-supporting surface into the plunger chamber. Referring to this construction, the numeral I designates the main shell of the unit and 2) designates the integral bottom thereof which serves as a support for the ice tray such as the tray a, the other trays not being shown in this view. Said unit isY y provided in the same manner as the unit shown in Figs. 1 and 2 with pressure plates which are applied to the compressed, attened, refrigerant coils 22 so as to maintain the latter in intimate contact with the bottom 2B. The nu- Ymeral 23 designates the depending integral boss carried by the bottom 2U, but as shown, the

` face of the plate 2Q, adjacent the aperture formed therein, is tapered, as designated by the numeral 24 and a screw plug 25, also having a tapered A upper surface 25. and carrying an integral, centrally disposed hollow boss 21. is threaded into said boss 23 and serves to rigidly secure between the tapered surfaces 2d and 26, a diaphragm 28 preferably formed of a metal, such as copper or phosphor bronze, such as commonly employed for flexible metal tubing and flexible metal bellows 5 and which is capable of withstanding innumerable flexings. A depending post 29 is riveted or welded to said diaphragm centrally thereof and adjacent its lower end is grooved peripherally to form a bottom head 29. y A spring-pressed plunger 30, hav- 10 ing a spiral thread 3i thereon similar to the thread c of Fig. l, is provided with a T-slot f at its upper end, the transverse portion of said slot being of a size to receive the said head 29 and the shank portion of said slot extending through from one 15 side of the head of the plunger 30 slightly beyond the center of the plunger, whereby when said plunger and post are assembled, as shown, the same are free to rotate relative to each other, but incapable of longitudinal movement relative to zo each other.

A set screw 32, having a reduced inner end 33, co-operates with said groove 3l to effect the longitudinal movement of the plunger and diaphragm carried thereby when the saidv plunger 25 is rotated. The lower end 34 of said plunger is tapped to receive a handle 35, which latter is normally retracted, as shown in Fig. 5, in the identical manner as is the handle I I shown in Fig. 1, by a coil spring I 4, which is secured by its respective 30 ends to a screw I5 and handle 35. 'Ihe to-andfro-movement of said handle 35 serves as in the case of the handle I I, to raise and lower the plunger 3B and the diaphragm 28 carried thereby,

which latter effectively precludes the seepage of 3:5Y

water into the central chamber of the plug 25 within which the plunger 3i) is mounted and it is never necessary to first fracture an ice bond formed between the plunger 30 and the surrounding wall of said central chamber in which the 40 same is mounted.

In order to operate the form of my improved tray lifting device shown in Figs. 1 to 4, as is apparent from the foregoing description, it is merely necessary to manually grasp the knob I2 45 and force the plunger into the tray lifting position shown in Figs. 2 or 3, whereupon the spring pressed plunger 'I is elevated into the position shown in Fig. 2, with the consequent fracture of any ice bond between the bottom of the tray en- 50 gaged by it and the bottom plate of the freezing unit, with the consequence that the tray is slightly lifted oif its support as shown in Fig. 2. The said plunger is machined so as to have a tight, sliding t within the cylinder 5 which, as above 55 stated, is drilled, and consequently the tendency for any water to penetrate into the interior of the cylinder 5 is very slight and furthermore, owing to the extremely small cross section of the end d of the set screw, even if there is a slight seepage 50 of water into the cylinder 5, any ice bond between the walls of the groove c and said end d is of negligible dimensions and easily fractured.

In addition to the advantages hereinbefore noted, may be mentioned the fact that in my improved construction the pressure reaction from the movement of the plunger element is virtually downward at a point centrally between the sides of each tray support and since the boss 5 is rigidly connected with the bottom plate, which is a very substantial element, there is no possibility of distortion of any of the parts of the cooling unit or of exerting any strains upon the joints connecting such unit with the refrigerant line, Furthermore, not only is the plunger element readily movable, but if the same is packed in a suitable, relatively hard water-proof grease, such as a hard cup-grease as commonly used in machinery, there will be little likelihood of sufficient water entering into the cylinder 6 to produce any substantial ice bond between the top or intermediate walls of the plunger and theA said cylinder. My improved device is so remarkably effective that, even though the ice bond is deliberately formed between the support and the tray by wetting the tray with water before inserting the same into the cooling unit, one can grip the knob I2 with the thumb and forefinger and with but the slightest effort rotate the plunger and elevate the same into the tray lifting position shown in Fig. 2, all without the possibility of any of the parts being distorted, displaced or strained.

While I prefer a plunger having a spiral groove thereon, which groove is considerably smaller than the spacing between the two adjacent turns of said groove, a plunger having a thread, preferably a square thread, thereon, may be substituted therefor. boss 5 be made integral with the bottom plate, but the same may consist of a sleeve having threaded engagement with the bottom plate, although the integral form of bo'ss is much to be preferred because of being more sanitary, since there is no joint between the boss and the bottom plate for the permanent lodgment of water or ice and wherein germs could propagate.

While it is preferable that the handle l l be returned to its original position automatically when the pressure applied to the knob l2 is relieved, as

"- thereby the device is rendered foolproof and there is no possibility that the plunger will be in an elevated position, when the tray is inserted into the tray chamber of the cooling unit, and maintain the tray so inserted out of intimate contact with its support, nevertheless, if desired, such spring may be omitted and in such an event, it would be necessary to always manually return the handle to the first or inoperative position before inserting an ice tray into the cooling unit.

Various other changes in the aforesaid construction may be made without departing from the spirit of my invention as embraced in the appended claims.

Having thus` described my invention, what I 1 claim and desire to obtain by United States Letters Patent is:

l. In a freezing unit for a refrigerating machine, the combination comprising a supporting surface for an ice tray, having a downwardly projecting hollow extension, a plunger member mounted in said extension and arranged, when in a certain position, to exert upward pressure directly upon the bottom of a tray resting on said J which is of the same diameter as that of the said aperture and is in register therewith, a plunger having a peripheral spiral groove thereon and means mounted on said extension and projecting n into said groove for effecting the to and fro longitudinal movement of said plunger within said Likewise, it is not essential that the bore upon manual rotation of said plunger, whereby the latter may be optionally elevated into a tray lifting position and any ice bond between the tray and its support simultaneously fractured. ":5

3. In an evaporator unit for refrigerating machines, the combination comprising a tray supporting surface and means for optionally elevating a tray off of said surface, including a vertically movable plunger having a spiral peripheral groove thereon and a co-operating element projecting into said groove and mounted independently of said plunger for effecting longitudinal to and fro movement of said plunger upon rotation thereof. 15z

4. In an evaporator unit for refrigerating machines, the combination comprising a tray supporting surface, having an integral downwardly projecting hollow boss formed thereon, a plunger element, having a spiral, peripheral groove formed thereon, mounted within said boss, a set screw, whose end is of a size to t in said groove, so mounted that such end can be projected into said groove and thereby co-operate with said plunger to effect its longitudinal movement upon 2'5i rotation of the plunger, and spring-actuated means for operating said plunger.

5. In an evaporator unit for refrigerating machines, the combination comprising a tray supporting surface, having an integral downwardly projecting hollow boss formed thereon, a plunger element, having a spiral, peripheral groove formed thereon, mounted within said boss, a set screw, whose end is of a size to fit in said groove, so mounted that such end can be projected int'o 355y said groove and thereby co-operate with said plunger to effect its longitudinal movement upon rotation of the plunger, and means for operating said plunger.

6. A cooling device, comprising in combination 40 l a chambered receptacle having a bottom adapted to serve as a support for an ice tray, a false bottom plate secured to the bottom of said receptacle, a refrigrant coil interposed betwen said bottom plate and said bottom of said receptacle, a hollow extension projecting from the bottom of the receptacle through the false bottom plate,

a plunger member mounted in said extension and adapted to be projected to a position above the level of the bottom of said receptacle and means for optionally effecting longitudinal to and fro movement of said plunger.

7. A cooling device, comprising a chambered receptacle, means for maintaining a refrigerant fluid in good heat exchange relation with a portion of said receptacle, an extension projecting downwardly from the bottom of said receptacle,

a movable element mounted in said extension whose upper end is adapted to be projected to a level above that of the bottom of said receptacle, said movable element having a peripheral spiral groove thereon, and means mounted independent of said movable element adapted to project into such groove and to co-operate therewith to effect the longitudinal to and fro movement of said movable element upon rotation of the latter.

8. In an evaporator, for a refrigerating apparatus, the combination comprising a receptacle for an ice tray having an apertured bottom adapted to serve as a support for such a tray, an integral hollow boss surrounding said aperture and projecting downwardly therefrom, a cylindrical plunger element of a maximum diameter suflicient to have a snug friction fit with said bottom aperture, said plunger having a spiral l peripheral groove thereon intermediate the ends thereof and having its upper end of a diameter equal to the maximum diameter ofl the plunger, a co-operating pin mounted in said extension, the inner end of which is of a dimension to t in said groove, a slotted baffle plate positioned at the front of said receptacle and an operating handle secured to the bottom plunger and projecting through said slot.

9. A cooling device, comprising a refrigerant coil, a cooling shelf in intimate contact therewith, said shelf having an aperture extending therethrough, a flexing diaphragm member sealing said aperture and a downwardly depending casing carried by said shelf, a spring-actuated plunger element, provided with an `operating handle, mounted within said casing and co-operating with said diaphragm 'for optionally projecting a portion of said diaphragm above the level of said shelf.

10. In an evaporator for a refrigerating apparatus, the combination comprising a receptacle for an ice tray, having an apertured bottom, adapted to serve as a support for such a tray, an integral, hollow boss surrounding said aperture and projecting downwardlytherefrom, a plug member mounted in said boss, a flexing diaphragm member extending across the aperture in said bottom member and rigidly secured at its margin between said plug member and said bottom element, a plunger element mounted in said plug member and secured to said diaphragm in such a manner that the same are rotatable relative to each other, but incapable of independent` longitudinal movement relative to each other and means for normally holding said plunger and said diaphragm in a depressed position so that the latter is normally held below the top of said bottom element.

11. In an evaporator for a refrigerating apparatus, the combination comprising a receptacle for an ice tray, having an apertured bottom, adapted to serve as a support for such a tray, a flexing diaphragm element extending across and sealing said aperture, means for optionally projecting said diaphragm above the normal level of said bottom element and means for normally vmaintaining said diaphragm in a depressed posi- `tion so that no portion thereof projects above the top level of said bottom element.

12. In an evaporator for a refrigerating apparatus, the combination comprising a receptacle for an ice tray, having an apertured bottom, adapted to serve as a support for such a tray, an integral hollow boss surrounding said aperture and projecting downwardly therefrom, a plug member mounted in said boss, a plunger element mounted in said plug, a flexing diaphragm element sealing the aperture in said bottom element, the said diaphragm being centrally secured in swiveled connection to the top of said plunger, means for normally maintaining said diaphragm in such a position that no portion thereof extends above the top level of said bottom element and means for normally projecting said diaphragm element to a position substantially above the top level of said bottom element.

13. In a freezing unit for a refrigerating machine, the combination comprising a supporting surface for a tray intended to receive a substance to be cooled, said surface being provided with an aperture intermediate the margins thereof, a hollow extension projecting downwardly from the bottom of said support, having a central bore, the axis of which is in alignment with the center of Asaid aperture, a plug member fitted into said extension and a plunger member carried by said Aplug member and'rotatably mounted therein, a diaphragm extending across said aperture and serving to seal the same against the entrance of moisture into said extension in which said plug is mounted, said diaphragm being loosely secured to said plunger so as to admit of relative rotation therebetween and means for elevating and depressing said plunger and said diaphragm with respect to said supporting surface.

14. In a freezing unit for a refrigerating machine, the combination comprising a tray-supporting surface having an aperturel intermediate the margins thereof, a diaphragm sealing said aperture, a plunger member secured to said diaphragm and carried by said tray-supporting surface, means for rotating said plunger relative to said diaphragm and thereby effecting the raising or lowering of said diaphragm with respect to said supporting surface in accordance with the direction of rotation of said plunger.

15. In an evaporator for refrigerating apparatus, the combination comprising an enclosure having a chamber therein adapted to receive a tray and the bottom of said chamber constituting a tray support and being apertured, a hollow extension projecting downwardly from the bottom of said enclosure, the longitudinal axis of the bore of which extension coincides with the center of said aperture, a plunger member having the whole external diameter corresponding substantially to the internal diameter of the bore of such extension, said plunger having a spiral groove thereon, a set screw extending through the wall of said extension and the end of the same being adapted to project into said groove when said screw is turned down to approximately its innermost limit of travel, and means for effecting the rotation of said plunger and thereby simultaneously causing the to and fro movement thereof within the bore of said extension.

16. In an evaporator for refrigerating apparatus, the combination comprising an enclosure having a chamber therein adapted to receive a tray and the bottom of said chamber constituting a tray support and being apertured, a hollow extension projecting downwardly from the bottom of said enclosure, the longitudinal axis of the bore of which extension coincides with the center of said aperture, a plunger member having the whole external diameter corresponding substantially to the in ternal diameter of the bore of such extension, said plunger having a spiral Vgroove thereon, a set screw extending through the wall of said extension and the end of the same being adapted to project into said groove when said screw is turned down to approximately its innermost limit of travel, and elastic means for normally maintaining said plunger in a depressed position so that the top level of Said plunger does not project above the top Surface of said tray support.

17. In an evaporator for refrigerating apparatus, the combination comprising a receptacle for an ice tray, having an apertured bottom, adapted to serve as a support for such a tray, an integral, hollow boss surrounding said aperture and projecting downwardly therefrom, a plug member mounted in said boss, a flexing diaphragm member extending across the aperture in said bottom member and rigidly secured at its margin between said plug member and said bottom element and a plunger element mounted in said plug member and secured to said diaphragm in such a manner that the same are rotatable relative to each other, but incapable of independent longitudinal movementl relative to each other.

18. A cooling device, comprising a refrigerant coil, a cooling shelf in intimate contact therewith, said shelf having an aperture extending therethrough, a exing diaphragm member sealing said aperture and a downwardly depending casing carried by said shelf, a plunger element mounted within said casing and co-operating with said diaphragm for optionally projecting a portion of said diaphragm above the level of said shelf.

19. In an evaporator for refrigerating apparatus, the same having a cooling shelf adapted to receive a tray, said shelf having an aperture extending completely therethrough, a boss projecting downwardly from said shelf, said boss having a central bore which conforms substantially to the aperture in said shelf, a plug member having threaded engagement with said boss, a diaphragm member rigidly secured between the top of said plug and the upper end of said boss, said diaphragm serving to seal the upper end of said boss against the entrance of moisture thereinto, a plunger member having swiveled connection with said diaphragm and projecting downwardly therefrom, said plunger member being mounted within said plug and means for effecting reciprocation of said plunger member and the consequent raising or lowering of said diaphragm with respect to the top surface of said cooling shelf.

20. In an evaporator unit for refrigerating machines, the combination comprising a tray-supporting member, a tray member intended to receive a substance to be cooled supported on said surface and means including a hollow extension secured to one of said members, the same having a vertical bore extending through the rbottom thereof, a plunger member mounted in said bore and means for effecting the spiral movement of said plunger within said bore, whereby the same may be optionally moved into a tray lifting position and any ice bond between the tray and its supporting member simultaneously fractured.

21. In an evaporator unit for refrigerating machines, the combination comprising a tray-supporting member, a tray member intended to receive a substance to be cooled supported on said surface and means including an extension formed on one of said members, the same having a bore extending through the bottom thereof, a plunger mounted in said bore and a handle for effecting the reciprocation of said plunger whereby the latter may be optionally moved into a tray lifting position and any ice bond between the tray and its supporting member simultaneously fractured.

SYLVESTER A. LIMPERT. 

